How can you pick the highest ranked people out of photos?

They appear the least cooperative:

In 3 studies, we tested the hypothesis that the higher ranked an individual’s group is, the less cooperative the facial expression of that person is judged to be. Study 1 established this effect among business school deans, with observers rating individuals from higher ranked schools as appearing less cooperative, despite lacking prior knowledge of the latters’ actual rankings. Study 2 then experimentally manipulated ranking, showing that the effect of rankings on facial expressions is driven by context rather than by individual differences per se. Finally, Study 3 demonstrated that the repercussions of this effect extend beyond the perception of cooperativeness to tangible behavioral outcomes in social interactions. Theoretical and practical implications of this phenomenon are discussed.